John Harrison explicitly says that she's twice the size of Enterprise, and I confirmed that by doing a comparison measurement of the two CGI models. So using that and other official numbers as a basis and using very rough visual estimates to get some ballpark numbers, here is what I get for the Dreadnought Class if we take the Enterprise's length at 760 meters or 2,500 feet the length given in the "Experience the Enterprise" promotional feature from the 2009 film's advertising campaign. I am also using a deck chart I found for the new Enterprise (at her enormous "official" length) online that gives her 39 decks and an average height of 4.1 meters per deck.
This ship is so big that her SAUCER alone is the length of the entire Enterprise, which as a Heavy Cruiser, counts as a medium sized ship. All numbers are rounded and heavily approximated and can change if we get official numbers released after the movie (which isn't likely given how sloppy the ST:09 designers are compared to the guys who worked on the previous productions).
*Name: USS (United Space Ship) Vengeance
*Launch Date: A.D. 2259 (Alternate Reality)
*Fate: Destroyed (damaged beyond repair by internal detonation of 72 Photon Torpedoes and crash-landed in San Francisco Bay)
*Hull Type: Warship
*Registry: N/A (Unmarked/Officially Nonexistent)
*Affiliation: United Federation of Planets
*Operator: Federation Starfleet (Section 31)
*Top Speed: presumably Warp Factor 12 (pre-TNG warp scale)
*Special Characteristics: Unspecified "Mark IV" Capabilities including, but possibly not limited to, advanced warp technology, next-generation sensor technology including "multi-dimensional RADAR" and "space region observer" systems, upgraded (potentially M5-level) automation of all primary systems and anti-transwarp beaming countermeasures, hull armor including extending plates to cover the navigational deflector and a "sunken" main bridge configuration
*Cargo Capacity: At least seven storage hangars w/ airlock hatches
*Weapons: High-yield multi-emitter rapid-firing ball-turret Phaser banks, Swivel-mounted Photon Torpedo launchers, Torpedo drones (missile-like weapons that fire a cluster of micro-torpedoes before impacting the target & detonating)
*Defenses: Upgraded deflector shields, Heavily armored outer hull
*Designer: "Commander John Harrison" (a.k.a. Khan Noonien Singh)
*Commanding Officer: Admiral Alexander Marcus, Starfleet Commander-in-Chief, Section 31 C/O (Unofficially)
*Construction Site: Classified Section 31 Spacedock orbiting Io (Coordinates 22.214.171.124)
*Crew Complement: Unknown (can be operated by one individual if necessary)
*Main Bridge: judebgallery.files.wordpress.c…
*Photon Torpedo Launcher: images3.wikia.nocookie.net/__c…
*NOTE: The Warp Factor scale is NOT linear. Therefore, Warp 12 is actually three times as fast as Warp 8. The existence of anti-transwarp beaming countermeasures on this ship has been personally confirmed by Roberto Orci. It explains why John Harrison had to flee to Qo'nos instead of beaming right to Io to steal the Vengeance directly.
(USS Vengeance stats assuming a 760-meter-long Enterprise, as stated in "Experience the Enterprise" )
Length: 1,520 meters
Beam (Saucer Diameter): 760 meters
Overall Height: 285 meters
Draft (Height, Discounting Nacelles): 200 meters
Deck Count (if decks are 4.1 meters tall): 48 decks
Deck Count (if decks are 8.2 meters tall): 24 decks
(USS Vengeance stats assuming a 2,379.75-foot-long Enterprise, as stated in the "Starships" featurette from ST:09)
Length: 1,462.11 meters
Beam (Saucer Diameter): 731.06 meters
Overall Height: 274.14 meters
Draft (Height, Discounting Nacelles): 192.4 meters
Deck Count (if decks are 4.1 meters tall): 46 decks
Deck Count (if decks are 8.2 meters tall): 23 decks
(USS Vengeance stats assuming a 725.35-meter-long Enterprise, as stated in "Star Trek: The Art of the Film" )
Length: 1,450.7 meters
Beam (Saucer Diameter): 725.35 meters
Overall Height: 272 meters
Draft (Height, Discounting Nacelles): 190.9 meters
Deck Count (if decks are 4.1 meters tall): 46 decks
Deck Count (if decks are 8.2 meters tall): 23 decks
I should point out that the fan-made chart I used for the AR Enterprise gave the Abrams version of Kirk's ship a total of 39 decks at 4.1 meters per deck. Of course, if the ship's decks are 8.2 meters tall, that would mean that the average deck on board the Vengeance would be 27 feet high. 4.1 meter decks are already 13.5 feet tall. Given that I'm a pretty average 25-year-old human male and I'm 5.67 feet tall (5'8"), if the Vengeance had 8.2 meter decks then the average level aboard ship would be four times my height.
According to information I've read elsewhere, many high-rise buildings will have floors that range from about 8.5 feet tall to anywhere from 10 to 12 feet tall while decks on many cruise ships, which need more space for hardware, may have average floor-to-floor heights of about 10 feet to up to 16 feet tall for more "public areas" such as, perhaps, a grand atrium, so the 4.1 meter height is pretty believable.
I don't know if I will use the 4.1 or 8.2 meter average floor-to-floor deck height if/when I do my own take on the Dreadnought hull plan. It is entirely possible that, as these futuristic warships need a lot of equipment hidden away beneath their floors and above their ceilings (otherwise it would not be possible to have those smooth corridors that are so typical of "Star Trek" - you never see those on a real-life Navy warship), that the floor-to-floor deck heights could indeed be, say, 8.2 meters, but that only 4 or 5 of those meters would actually be habitable, and this isn't even counting the more cavernous parts of the ship that would definitely need to be that large, like Main Engineering or the Shuttle Bay.
Now, all of this was horribly misconstrued because of the infamous "shuttle bay scene" from the 2009 film where the Enterprise is seen as holding anywhere from 16 to 20 or more military transport shuttlecraft in a giant hangar bay. The ST:09 Enterprise was originally designed to match up with the Refit Enterprise from the 1979 Motion Picture. Her saucer decks and the shape of her hull scaled appropriately and most of the extra length (the Enterprise Refit measured around 300-302 meters or so while this ship was 366 meters) came from her much longer warp nacelles. But the shuttle scene posed a giant problem that wouldn't go away. Matt Jefferies' original designs for the Enterprise's shape did not give the ship's aft the capacity to hold anywhere near that many small craft. She could maybe fit 4 shuttles on the floor and have 2 or 3 more below decks in disassembled condition, and those shuttles were barely large enough to fit seven people, making them about the size of a minivan or a Chevy Astro if you want to be generous about it.
But the new ST:09 "military bus" shuttles are much, much bigger, easily capable of fitting up to 40 passengers plus cargo and a flight crew or even containing an entire laboratory (Scotty's shuttle doubled as his lab). I would guess these shuttles must be about the size of a Greyhound bus. And there was no way that a 366 meter Enterprise could hold 16-20 of those things with room to spare. Therefore, the awful and very arbitrary decision was made, in the interest of keeping the "drama" and "heroism" of the shuttle scene - overblown scaling and all - to simply blow up the size of the Enterprise to anywhere from 725.35 to even 760 meters instead of redoing the shuttle scene with fewer shuttles and explaining that the rest of the crew beamed aboard instead (which would have been perfectly acceptable). We now have a 2258-era Constitution-Type Class I Heavy Cruiser as big as an Old Republic Acclamator Class Assault Transport and there's something very wrong with that, especially since the physical architecture of the CGI model still suggests a 302-366 meter ship with maybe 19-20 decks (if the decks are still 4.1 meters tall on average). Engineer Berndt Schneider, a very respected Trekkie and webmaster of the "Ex Astris Scientia" site, therefore prefers to take the Enterprise at a much smaller scale of around 302 meters to match her up with the Enterprise Refit as it's a more realistic scale.
However, that's what the "Powers That Be" say, so the Enterprise became a giant vessel with a 1,100-man crew (the original TOS Enterprise went from a crew complement of 203 in "The Cage" to a little over 400 by TOS proper, so the new ship has nearly three times her crew complement) in the 2009 film. Now, back to our discussion of starship scaling. I did some (again, very rough) recalculations and if the Enterprise is taken to be 366 meters long as she was originally designed, and therefore given a crew complement based on the original ship's, her basic stats would look like this:
U.S.S. Enterprise (NCC-1701), Alternate Reality 2258
Overall Length: 366 meters
Beam (Saucer Width): 164 meters
Overall Height: 92 meters
Draft (Height w/o Nacelles): 77 meters
Average Deck Height: 4.1 meters
Deck Count: 20 decks
Crew Complement: ~430 officers & enlisted ratings
And if we keep the same scaling when recalculating the basic design specifications for the Dreadnought Class, she measures in at a size that, while still enormous for AR 2259, is much more "appropriate" for "Star Trek" because it's comparable to a Sovereign Class Explorer from PR 2371 (and, again, the Acclamator Class Assault Ship from "Star Wars" Episode II). Of course, we don't know her intended crew complement at this time, only that she needs "much less" personnel to crew her than Enterprise did due to dramatically improved automation. The U.S.S Vengeance herself from "Into Darkness" appears to be only manned by a skeleton crew at that, so I don't think we can take her as a typical example of a Dreadnought Class fully manned at maximum combat readiness. So, if we assume a 366-meter Enterprise, here's what we get:
U.S.S. Vengeance (Unknown Registry), Alternate Reality 2259
Overall Length: 732 meters
Beam (Saucer Width): 366 meters
Overall Height: 138 meters
Draft (Height w/o Nacelles): 97 meters
Average Deck Height: 4.1 meters
Deck Count: 24 decks
Crew Complement: Unknown standard complement; the ship is capable of being run by a single operator.
Of course, this is all a wild ballpark guess based on known numbers from both ships, a presumptive fan-created deck chart for the Alternate Reality U.S.S. Enterprise (NCC-1701) and my own eyeballing of the relative sizes between the two CGI models from what few screen shots we have of the two ships together, as well as the proportions of the U.S.S. Vengeance CGI model. J.J. Abrams' staff have not been very good at calculating or releasing information about the sizes of their ships in the new "Trek" franchise and even when they do, they only give us a bare minimum of information, leaving us to calculate the rest ourselves. (It took quite a while to finally get an official length for U.S.S. Kelvin (NCC-0514) at 452 meters, for example.) But, until we *do* get official numbers, this is the best I can do and it's what I'll assume when I go to see the movie in mid-May 2013.
04/25/2013 (Updated 06/02/2013)
UPDATE (06/04/2013): Memory Alpha has noted that Quantum Mechanix was contracted to build a series of spacecraft and starship models to illustrate the "history of space flight." These models can be seen briefly on the desk of CINCFLEET Admiral Alexander Marcus' little office during a meeting between Kirk, Spock and Marcus at Starfleet Headquarters following John Harrison's assault on the Daystrom Building.
The U.S.S. Vengeance appears as one of these models, but co-writer Roberto Orci has confirmed in correspondence that this ship shouldn't have been there because as an unmarked, unregistered, exclusively Section 31 design, the Vengeance - and any other Dreadnought-class starships that may have been built by S31 prior to Harrison's revolt - should not "officially" exist in Federation records and, therefore, no image of the ship should be found in such a public location (remember, Section 31 doesn't officially exist). Orci has stated personally that had he been on set that day, the model of Vengeance would have been removed, but as a close-up shot of the model made it into the final film, it's canon and its existence cannot be retracted.
Orci decided to clear up the issue by stating that the while the finished Dreadnought-class design as seen with U.S.S. Vengeance was indeed a top-secret experimental prototype, it may not represent a design that was thought up by Khan Noonien Singh and S31's design boards entirely from scratch during the short 1-year gap between "Star Trek (AR 2258)" and "Star Trek: Into Darkness (AR 2259)." Instead, it is more likely that an earlier, more primitive, unfinished version of the Dreadnought-class design had been partially developed and proposed during the quarter-century's worth of technological innovations and new ideas that led to the development of the AR Constitution-Type Class 1 Heavy Cruiser, but then shelved (for whatever reason) until after the destruction of Vulcan and the discovery of S.S. Botany Bay.
Then, after his awakening, Section 31 would have taken this existing (and, judging from the model, likely publicly known) design out of mothballs and had Khan Noonien Singh (under the cover identity of Commander John Harrison) work on the unnamed existing design, dramatically enlarging the ship to twice the length of the Constitution Type and adding an entire host of technological innovations developed using Khan's superior intelligence, from the "Mark IV" suite of advanced warp, computer, sensor and transporter capabilities to the improved multi-emitter Phaser turrets and swivel-mounted heavy torpedo launchers.
Width: 2400 feet (731.52 meters)
Height: 1133.33 feet (345.34 meters)